There hasn't been a more controversial pick for secretary of education, arguably, in recent memory than Donald Trump's choice of Betsy DeVos. The Senate confirmation hearings for the billionaire Republican fundraiser and activist from Michigan start today.

DeVos is a champion of vouchers and expanding charter schools in a broader push for greater school choice — closely aligned with the views of the president-elect.

Her hearing was pushed back nearly a week because of Democrats' concerns over her "extensive financial entanglements and potential conflicts of interest," as Sen. Patty Murray of Washington put it. She's the top Democrat on the Senate Health, Education, Labor & Pensions Committee, which will conduct the hearing.

Here are five areas of questioning that are likely to come up:

1. Money

DeVos and her family have given more than a million dollars to sitting Republican senators, according to Federal Election Commission reports, as well as some $10 million more to superPACs and party committees.

That has prompted numerous left-leaning groups, including End Citizens United, to call for some senators to recuse themselves on a DeVos confirmation vote.

Given that DeVos once said she expects a return on investment for contributions, expect Democrats to challenge her on how the DeVos family has used its billions to support ballot measures, organizations, causes and politicians in Michigan, as well as some of the elected officials who'll be sitting in front of her.

2. ESSA

Expect tough questions on President-elect Trump's call for redirecting some $20 billion in federal aid to school choice. Trump has yet to put any meat on the bones of that idea. DeVos will certainly be asked whether that idea might mean redirecting money from federal Title I programs for the poor and disadvantaged. Or whether the new administration will seek to reopen the Every Student Succeeds Act, which passed with rare bipartisan support in 2015.

Supporters, however, say DeVos has the leadership and vision to radically shake up the federal education bureaucracy, foster change and further return power to the states.

"Betsy has worked for years to improve educational opportunities for all children," is how Lamar Alexander, R-Tenn., put it. He's the former education secretary who chairs the committee. "As secretary, she will be able to implement the new law fixing No Child Left Behind just as Congress wrote it, reversing the trend to a national school board and restoring to states, governors, school boards, teachers, and parents greater responsibility for improving education in their local communities."

Michigan has one of the least-regulated charter programs in the country and critics point to Detroit's troubles as one outcome of that. The state also has a high proportion of charter schools run by for-profit organizations. That's thanks, in part, to the advocacy and funding by DeVos, her family and the organizations they've supported.

Sen. Murray put it this way in a release, after meeting with DeVos earlier this month: "I continue to have serious concerns about her long record of working to privatize and defund public education, expand taxpayer-funded private school vouchers, and block accountability for charter schools, including for-profit charter schools."

GOP senators on the committee, meanwhile, seem thrilled that a strong advocate of greater school choice is before them. "Looking forward to working with her," Kentucky's Rand Paul tweeted after DeVos was nominated.

"If confirmed, would you use your position as Secretary of Education to promote the expansion of private school voucher programs in public education?" Sen. Elizabeth Warren of Massachusetts asked in a 16-page letter listing more than 40 issues and questions she plans to bring up.

Conservatives, meanwhile, are elated that they have a nominee who they believe will stand up to teachers unions they see as major impediments to choice and change.

5. Higher ed

Where does DeVos stand on key higher ed issues of access, debt, affordability and accountability that got lots of attention during the presidential race?

During the campaign, Trump did tell supporters at a rally, "If the federal government is going to subsidize student loans, it has a right to expect that colleges work hard to control costs and invest their resources in their students. If colleges refuse to take this responsibility seriously, they will be held accountable."

Asher hopes nominee DeVos voices support for continued tough oversight of for-profit colleges, something the Obama administration prioritized. "Making sure that students including veterans and service members should be protected from waste, fraud and abuse plays directly into college affordability," Asher says.

DeVos is likely to get questions on one of the only higher ed proposals the Trump campaign outlined during the race: an income-driven repayment plan for federal student loans that caps a borrower's payment at no more than 12.5 percent of his or her monthly income. Remaining debt after 15 years of payments would be forgiven under Trump's plan.

Sen. Alexander says that in higher ed, too, he's hoping DeVos will reduce bureaucracy and help "clear out the jungle of red tape that makes more difficult for students to obtain financial aid."